asList 추가

src/main/java/cokr/xit/foundation/util/ListSupport.java

@@ -1,6 +1,7 @@
 package cokr.xit.foundation.util;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.function.Consumer;
 import java.util.stream.StreamSupport;
@@ -25,14 +26,23 @@ public class ListSupport<T> {
 		return this;
 	}
 
+	/**iterable을 List로 변환하여 반환한다.
+	 * @param iterable Collection
+	 * @return List
+	 */
+	public List<T> asList(Iterable<T> iterable) {
+		return iterable == null ? Collections.emptyList() :
+			iterable instanceof List<T> ?
+			(List<T>)iterable :
+			StreamSupport.stream(iterable.spliterator(), false).toList();
+	}
+
 	/**List로 변환할 Collection을 설정한다.
 	 * @param iterable Collection
 	 * @return 현재 ListSupport
 	 */
 	public ListSupport<T> setIterable(Iterable<T> iterable) {
-		this.list = iterable instanceof List<T> ?
-			(List<T>)iterable :
-			StreamSupport.stream(iterable.spliterator(), false).toList();
+		this.list = asList(iterable);
 		return this;
 	}